In the computer.
Look at your error codes again. It should read something like "quad driver module FAULT" not failure. It is VERY unlikely that your quad driver actually died. It is the high power control system that is in your computer. So replacing it, means replace the computer. To prevent this the Quad Driver has all sorts of internal protection hardware in its design. The likely thing that is wrong is something the Quad Driver is connected to. And that The quad driver isn't seeing every thing correctly so thus the Fault. It also can fault if there is a wiring problem from the device to the quad driver. There are Test for each component. You should to to find out which is the problem. Consult your Shop Manual.
If a quad driver has gone bad it is necessary to replace the ECM. After replacing the ECM, drive the car on a bumpy road and note whether the check engine light comes on. If it does, fix the problem or you end up with a repeat QDM failure. == == == == There is no such thing as a quad driver module. There are quad DRIVERS in the ecm.